Netwrix
netwrix.com › en › resources › blog › biggest-cyber-attacks-in-history
The Largest and Most Notorious Cyber Attacks in History
August 12, 2025 - Cyber attacks are deliberate attempts to steal, alter, or destroy data or to disrupt operations and to damage the digital parts of a critical infrastructure. This blog post explores the most destructive major cyber attacks in history, detailing the underlying motives and impact, and then offers prevention and detection best practices.
Pentest People
pentestpeople.com › blog-posts › the-top-5-most-dangerous-cyber-attacks-of-all-time
The Top 5 Most Dangerous Cyber Attacks of all Time
June 16, 2025 - The Top 5 Most Dangerous Cyber Attacks of all Time - Alex ArchondakisThis blog outlines the top 5 most dangerous cyber attacks of all time including The WannaCry Ransomware attack and The Equifax Data Breach and more attacks that have struck history.
The 5 Most Devastating Cyber Attacks
Fackin Jonathan James.
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July 21, 2018The Biggest Internet Attack in History
So why was he hit so hard? What are the israeli arrests and who is the former anti-dos dos-er?
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February 12, 2014We had a security incident. Here's what you need to know.
In other news, we hired our very first Head of Security, and he started 2.5 months ago. I’m not going to out him in this thread for obvious reason, and he has been put through his paces in his first few months. So far he hasn’t quit.
On a related note, if you’d like to help out here and have a security background, we actually have a couple of open security roles right now.
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Cloud Security Engineer
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Threat Detection Automation Engineer
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December 5, 2016Hackers demand $70 million to end biggest ransomware attack on record
Experts say it was no coincidence that REvil launched the attack at the start of the Fourth of July holiday weekend, knowing U.S. offices would be lightly staffed. Many victims may not learn of it until they are back at work on Monday. Most end users of managed service providers "have no idea" whose software keep their networks humming, said Voccola,
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August 28, 2019What is the biggest cyberattack in history?
The biggest cyberattack in history was arguably the Jonathan James attack on NASA and the U.S. Department of Defense in 1999, especially due to the fact that the attack compromised such trusted, high-profile organizations.
fortinet.com
fortinet.com › resources › cyberglossary › most-notorious-attacks-in-the-history-of-cyber-warfare
Top 5 Most Notorious Attacks in the History of Cyber Warfare | ...
What is the most famous cyberattack?
The most famous cyberattack is the Google China hack in 2009.
fortinet.com
fortinet.com › resources › cyberglossary › most-notorious-attacks-in-the-history-of-cyber-warfare
Top 5 Most Notorious Attacks in the History of Cyber Warfare | ...
Where did cyber warfare originate?
Cyber warfare may have originated in the United States when Americans supposedly took out Iranian nuclear facilities.
fortinet.com
fortinet.com › resources › cyberglossary › most-notorious-attacks-in-the-history-of-cyber-warfare
Top 5 Most Notorious Attacks in the History of Cyber Warfare | ...
Videos
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Top 10 Cyber Attacks In History | Biggest Cyber Attacks Of All ...
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Top 10 Cyber Attacks In History | Top 10 Cyber Attacks Of All Time ...
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The 5 Biggest Cyber Attacks in History - YouTube
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Top Cyber Attacks in History and Case Study - YouTube
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The Biggest Hack in US History: SolarWinds Hack - YouTube
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The Most Destructive Hack Ever Used: NotPetya - YouTube
Wikipedia
en.wikipedia.org › wiki › List_of_cyberattacks
List of cyberattacks - Wikipedia
3 weeks ago - Shamoon, a modular computer virus, was used in 2012 in an attack on 30,000 Saudi Aramco workstations, causing the company to spend a week restoring their services. Wiper – In December 2011, the malware successfully erased information on hard disks at the Oil Ministry's headquarters. Stuxnet, a malicious computer worm believed to be a jointly built American-Israeli cyber weapon.
Fortinet
fortinet.com › resources › cyberglossary › most-notorious-attacks-in-the-history-of-cyber-warfare
Top 5 Most Notorious Attacks in the History of Cyber Warfare | Fortinet
Keep sensitive data and anything ... will do less damage. The biggest cyberattack in history was arguably the Jonathan James attack on NASA and the U.S....
Center for Strategic and International Studies
csis.org › csis programs › strategic technologies program
Significant Cyber Incidents | Strategic Technologies Program | CSIS
2 weeks ago - October 2025: The ransomware group Medusa claimed responsibility for a data breach involving SimonMed Imaging, during which hackers exfiltrated data belonging to approximately 1.2 million patients. The attackers reportedly demanded $1 million to delete the stolen files, and SimonMed has brought in cybersecurity experts to investigate.
FBI
fbi.gov › investigate › cyber › major-cases
Major Cases — FBI
November 15, 2016 - In 1988, a graduate student unleashed the first major attack on the Internet and became the first person convicted of a new type of crime.
CM Alliance
cm-alliance.com › cybersecurity-blog › top-10-biggest-cyber-attacks-of-2024-25-other-attacks-to-know-about
Top 10 Biggest Cyber Attacks of 2024 & 25 Other Attacks to Know About!
This breach stands as one of the largest in Australian history, surpassing previous incidents such as the 2022 Optus hack, which impacted 10 million Australians. 6. Synnovis-NHS Cyber Attack: On June 4, 2024, the NHS in the UK declared a ‘critical incident’. Its pathology services provider, ...
Skillsoft
skillsoft.com › home › blog › a history of the worst cyberattacks
A History of the Worst Cyberattacks
October 23, 2024 - In response to the attack, Sony ... with stronger infrastructure. Affecting more than three billion people, the Yahoo cyberattack in 2013 is considered to be the largest data breach in history....
VikingCloud
vikingcloud.com › blog › biggest-cyber-attacks-in-history
The Biggest Cyber Attacks in History
The breaches occurred largely through hackers manipulating cookies to bypass authentications – with the second major breach, attackers even copied the user account database! Yahoo followed up the breach by appointing data security staff, upgrading security protocols, and advising users to reset their passwords. Stuxnet remains a fascinating case from a cyber security history perspective. First emerging around 2010, this intrusive worm was specifically developed to exploit vulnerabilities in Microsoft’s Windows OS.
Cobalt
cobalt.io › blog › biggest-cybersecurity-attacks-in-history
11 Biggest Cybersecurity Attacks in History
September 30, 2025 - Explore the 11 biggest hacker attacks in history highlighting breaches such as the 1999 attack on NASA or cyberattack that shut down an oil processing facility.
G2
learn.g2.com › biggest-cyber-attacks-in-history
22 Biggest Cyber Attacks in History That Made Global Headlines
June 24, 2025 - Discover the 22 biggest cyber attacks from 2011 to 2024, including how they happened, who was hit, and what they reveal about cybersecurity today.
AstrillVPN
astrill.com › home › biggest cyber attacks ever made in history
Biggest Cyber Attacks Ever Made in History - AstrillVPN Blog
October 21, 2025 - So there you have it – the 18 biggest cyber attacks in history.
Outpost24
outpost24.com › home › blog › the top 10 list of the world’s biggest cyberattacks
The top 10 list of the world's biggest cyberattacks
May 21, 2025 - A direct result of this is that the firm was bought by Verizon in 2017 for $ 4.5 million instead of the $ 4.8 million announced in 2016. Update (Dec 2018): Yahoo has now admitted that all of the 3 billion user accounts had been hacked in 2013. This ...
Monroe University
monroeu.edu › news › cybersecurity-history-hacking-data-breaches
Cybersecurity History: Hacking & Data Breaches | Monroe University
The biggest data breaches in history have occurred since 2005.
Information is Beautiful
informationisbeautiful.net › visualizations › worlds-biggest-data-breaches-hacks
World’s Biggest Data Breaches & Hacks — Information is Beautiful
June 1, 2022 - Data visualization of the world biggest data breaches, leaks and hacks. Constantly updated. Powered by @VizSweet.
UpGuard
upguard.com › blog › biggest-data-breaches-us
Biggest Data Breaches in US History (Updated 2025) | UpGuard
3 weeks ago - In one of the largest cyberattacks in US history, over 30,000 US businesses were affected by a sweeping attack on the Microsoft Exchange email servers, one of the largest email servers in the world.
TCecure
tcecure.com › home › the top 6 most expensive cyber attacks in history
The Top 6 Most Expensive Cyber Attacks in History - TCecure
March 5, 2024 - The VA made several cybersecurity mistakes, like not encrypting their data, which led to the physical theft of patient records for 26.5 million veterans, military personnel, and their families. ... In 2000, 15-year-old Michael Calce, aka Mafiaboy, unleashed a DDoS attack on high-profile websites like Amazon, CNN, eBay, Yahoo!, and Dell.
Clear Insurance
clearinsurance.com.au › home › business insurance › 10 biggest cyber attacks in history
10 Biggest Cyber Attacks in History | Clear Insurance
June 19, 2023 - The Adobe cyber attack was first thought to have breached the data of 2.9 million users. Moreover, it compromised the personal data of up to 38 million users! Adobe claims that only the passwords and credit card information of the first 2.9 million users were compromised, however, the remaining 35.1 million suffered the loss of their passwords and user IDs. In 2014, Yahoo was subject to one of the biggest cyber attacks of the year when 500 million accounts were compromised.
Infosecurity Europe
infosecurityeurope.com › en-gb › blog › threat-vectors › biggest-cyber-attacks.html
The Top 10 Biggest Cyber-Attacks and Their Impact
This article sets out 10 occasions that cyber-attacks severely impacted the lives of ordinary citizens, highlighting the growing link between the cyber and physical worlds. In December 2015, during the heart of winter, Russian threat actors compromised power distribution companies in western Ukraine, leading to a power outage for more than 230,000 residents.